Card-type, tag-type and coin-type semiconductor devices, which have semiconductor chips mounted thereon, are widely spreading to the industries, such as transportation, distribution and communications for their large information capacity and high security performance. Above all else, non-contact communication type semiconductor devices, which have recently been developed, are gaining popularity because of their characteristics. Specifically, outside terminals are not provided on the substrate, power is supplied from the reader/writer to the card by wireless, and signals are exchanged by wireless between the reader/writer and the card. For this reason, the outside terminals are primarily not subject to damage as are the contact type semiconductor devices, and the non-contact devices are easier to handle during storage and so on, and can stand long periods of use, less vulnerable to falsification of data and superior in security performance. Therefore, the non-contact semiconductor devices are expected to be employed in a wider range of applications.
As the semiconductor chips mounted on non-contact semiconductor devices of this kind, those semiconductor devices have been used which are not provided with an antenna coil for non-contact communications to receive power supply from an external device without contact and to send and receive signals to and from the external device without contact. Recently, as shown in FIGS. 16 and 17, there has been proposed a semiconductor chip of coil-on-chip type 1 in which a rewiring layer 3 is formed on a circuit-formed surface through an insulating layer 2, and an antenna coil 4 made up of the rewiring layer 3 is formed integral with the chip.
If a coil-on-chip type semiconductor chip 1 is used, it becomes unnecessary to provide an antenna coil separately and, therefore, it is unnecessary to connect the antenna coil to the semiconductor chip and take some measure to protect this connection. This facilitates the manufacture of non-contact semiconductor devices, and reduces production cost.
In late years, there has been proposed a chip scale package type semiconductor chip (hereafter referred to as a CSP) 8 as a semiconductor chip to be mounted on semiconductor devices regardless of whether they are of non-contact type or contact type. As shown in FIGS. 18 and 19, the CSP type semiconductor chip is produced by a following procedure. A rewiring layer 3 is formed, through an insulating layer 2, on a circuit-formed surface of a semiconductor chip which has a plurality of input/output terminals (pads) 5 formed along the periphery of the semiconductor chip, and bump-setting wires 6 are formed from the rewiring layer 3 and are laid out on the whole surface of the semiconductor chip. Each bump-setting wire 5 is connected at one end to an input/output terminal 5 and has a corresponding bump 7 formed at the other end of the wire.
If this CSP type semiconductor chip 8 is used, the bumps 7 can be laid out freely on the whole surface of the semiconductor chip 8, for which reason the array pitch and the size of bumps 7 can be made larger than in a case where the bumps 7 are formed on the input/output terminals 5 placed along the periphery of the semiconductor chip, and the number of the input/output terminals 5 can be increased and flip-chip mounting of semiconductor chips can be made easier.
Incidentally, as shown in FIGS. 16 and 18, the parts provided in separate blocks, marked off on the circuit-formed surface of the semiconductor chip to be applied to a semiconductor device, are a power circuit 11, an operational amplifier (Op-Amp) 12, a comparison amplifier (comparator) 13, an RF receiving part 14, an RF transmitting part 15, an RF synthesizer 16, a logic block 17, and a memory block 18. When a higher security performance is required, a microprocessor is sometimes included. The power circuit 11, the operational amplifier 12, the comparison amplifier 13, an RF receiving part 14, an RF transmitting part 15 and the RF synthesizer 16 are most often formed by analog circuits. When the memory block 18 is formed by EEPROM memory elements, for example, an analog circuit, such as a voltage build-up circuit or an amplifier circuit, is included as a part of the memory block circuit. On the other hand, the logic block 17 is most often composed of digital circuits. Note that among the well-known semiconductor chips for use in semiconductor devices, there are some examples, in which a coil section is included as a part of the analog circuit.
In a coil-on-chip type semiconductor chip 1 and a CSP type semiconductor chip 8, which have a rewiring layer 3 formed integral with the chip, the circuit-formed surface of the semiconductor chip 1 or 8 and the rewiring layer 3 are formed close to each other through an insulating layer 2 of a relatively high dielectric constant, and therefore a parasitic capacitance C is formed between the circuit and the rewiring layer 3 as schematically shown in FIG. 20.
However, in a conventional coil-on-chip type semiconductor 1 and a conventional CSP type semiconductor chip 8, consideration has not been given to adverse effects when a parasitic capacitance C is formed at a position where an analog circuit is formed, and therefore the antenna coil 4 or the bump-setting wires 6 are formed face-to-face with the analog circuit as shown in FIGS. 16 through 19.
Therefore, in the conventional coil-on-chip type semiconductor chip 1 and CSP type semiconductor chip 8, parasitic capacitances C are formed between the analog circuit on the circuit-formed surface and the rewiring layer 3, and as electromotive force (AC) generated in the rewiring layer 3 is coupled with the parasitic capacitances C, electrostatic induction noise is produced, and moreover, crosstalk noise, ringing (LC resonance shift), power source noise or the like ascribable to the electrostatic induction noise occur. Owing to all such hindrances, those semiconductor chips are liable to malfunction and deteriorate in the communication characteristics.
In the conventional coil-on-chip type semiconductor chip 1 and CSP type semiconductor chip 8, the circuit-formed surface is formed across the insulating layer 2 from the rewiring layer 3, and for this reason electrostatic induction noise is likely to occur in circuits provided on the circuit-formed surface, and malfunction and communication performance deterioration tend to occur.
Noise, such as crosstalk noise, ringing and power source noise ascribable to the electrostatic induction noise or electromagnetic induction noise has significant impacts on the analog circuits, such as the power circuit 11, the operational amplifier 12, the comparison amplifier 13, the RF receiving part 14, the RF transmitting part 15, and the RF synthesizer 16, particularly on the operational amplifier 12 and the comparison amplifier 13 handling minute voltage waveforms, the voltage build-up circuit or the amplifier circuit included in the memory block 18 that handles micro signals, and the coil. Noise of those kinds has more serious effects on the circuits that handle higher frequencies of voltage waveforms and signals. For this reason, with high-frequency-compatible semiconductor chips that can be applied to cell phones, for example, it is necessary to suppress the occurrence of noise of the kinds mentioned above.
The present invention has been made to solve those problems and has as its object to provide a semiconductor chip of rewiring layer-integral type capable of preventing malfunction due to noise and deterioration of communication characteristics, and also provide a semiconductor chip with excellent communication characteristics.